Quantum resource studied from the perspective of quantum state superposition

TL;DR

This paper explores quantum resources like discord and entanglement through the lens of quantum state superposition, defining local and nonlocal superpositions and linking their presence to classicality and separability.

Contribution

It introduces a unified framework for quantum resources based on superposition, distinguishing local and nonlocal superpositions and their roles in quantum state classification.

Findings

LS vanishes iff the state is classical

NLS vanishes iff the state is separable

Provides a unified perspective on quantum resources

Abstract

Quantum resources,such as discord and entanglement, are crucial in quantum information processing. In this paper, quantum resources are studied from the aspect of quantum state superposition. We define the local superposition (LS) as the superposition between basis of single part, and nonlocal superposition (NLS) as the superposition between product basis of multiple parts. For quantum resource with nonzero LS, quantum operation must be introduced to prepare it, and for quantum resource with nonzero NLS, nonlocal quantum operation must be introduced to prepare it. We prove that LS vanishes if and only if the state is classical and NLS vanishes if and only if the state is separable. From this superposition aspect, quantum resources are categorized as superpositions existing in different parts. These results are helpful to study quantum resources from a unified frame.